Switch mode power supply (SMPS) inductors such as the SPB-313 are also known as filter inductors, and are commonly used by design engineers to filter the output waveform signals of switching supply circuits. Using a bobbin (or drum) core design, the SPB-313 inductor is a printed circuit part rated at 900 µHy at 3.4 DC amps and has a maximum DCR of 0.226 Ω. The ferrite core material is very stable thanks to a high flux density saturation characteristic that exhibits small changes in inductance from 0DC to its rated DC current. Depending on the application, this part may be suitable for SMPS frequencies up to 250KHz.
These non-shielded inductors are considered open frame and have a lead size of 20 AWG. Nominal dimensions are: Core Diameter of 0.955” / 24.26 mm and Core Height of 0.975” / 24.77 mm. The radial leads have a center-to-center dimension of 0.775 inches / 19.69 mm and extend 0.6875” / 17.46 mm to 0.8125” / 20.64 mm from the mounting core surface. Furthermore, the leads are tinned to within 0.063” / 1.6 mm from where they exit the core itself. If additional securing is necessary, the core has a centrally located through-hole for mounting the part to the printed circuit board with a non-metallic #4 screw.